How To Find Roof Slope Factor

Examine your roof and look for a safe place to climb.

How to find roof slope factor.

Outside of the u s a degree angle is typically used. Roof length including overhangs 40. You don t have to climb a ladder and place a tape measure on the ridge and measure down to the base to find the length of the roof. For any roof slope expressed as x in 12 rise in run the hip and valley factor is determined by finding the square root of rise run 2.

The roof slope factor can be determined through sections 7 4 1 through 7 4 4 of asce 7 10 and can be known as. The most precise way to find the roof s slope is by measuring it from the underside. Roof pitch is a determining factor for cost of the roof as well as the roof area and the type of materials used. For instance a 7 12 roof pitch means that the roof rises 7 inches for every 12 horizontal inches.

The area of this roof 1073 3 sq. Multiply this amount by the slope factor 960 1 1180 1073 28. How do you calculate the slope of a roof. Simply locate a roof rafter board place the end of the level against the bottom edge and measure from the 12 inch mark vertically to the bottom edge of the rafter.

Gable wall length including overhangs 24. Using a tape measure make a pencil mark 12 inches from the end of a carpenter s level. Climb up the ladder and onto the. Then you ll be able to measure slope from an unfinished attic space under the roof.

Locate the level s 12 inch mark. Enter 6 into the calculator slope factor 1 1180. Multiply the result by the factor and this is the length of the roof from base to ridge. Warm roof slope factor cold roof slope factor.

You want to find out how much longer that length is than the 12 inches and express the difference as a number the roof slope factor also called the roof slope multiplier roof pitch factor or roof pitch multiplier. The roofing material should look dry and intact. How to determine roof slope factor 1. Use a level against the underside of the rafter you re measuring to get the most accurate value.

The roof slope factor is dependent on various roof properties including temperature shape and material. Use the factor instead. Multiply the roof length by the gable wall length 40 24 960. Once you know the roof slope multiplier for a particular slope you can use it to find the actual area of any size sloped roof.

Hold out your arms and hands perpendicular to the ground as you stand. Access one of the rafters then take.